Method of forming pistons



Jan. 2, 1923.

,W. G. HEGINBOTTOIVI.

METHOD OF FORMING PISTONS.

FILED JULY 15, 1920.

Patented Jan. 2, 11923.

UNITED stares PATENT QFFHGEO WALTER G. HJEGINBOTTOM, 01E FLINT,MICHIGAN, ASSIGNOR F ONE-I413 T0 JACOB R. FRANCIS, 01E FLINT, MICHIGAN.

METHOD OF FORMING PISTONS.

Application filed July 15,

To all whom it may concern:

Be it known that I, VALTER G. HEoINBoT- TOM, a citizen of the UnitedStates, residing at Flint, in the county of Genesee and State ofMichigan, have invented certain new and useful Improvements in Methodsof Forming Pistons. of which the following is a specification. referencebeing had therein to the accompanying drawing.

This invention relates to a method of forming pistons constructed inaccordance with the invention disclosed in my application for springpiston filed June 16, 1920, Serial No. 389,517, the object being toprovide a method by means of which a piston can be formed very cheaply.

A further object of the invention is to provide a method of forming asprlng piston wherein the piston is provided with guide portionsconnectedto the disk shaped portion of the head in such a manner thatthe guide portions can expand and contract so as to fit the cylinder ofthe internal combustion engine in order to prevent piston 5 slap.

Another and further object of the invention is to provide a method offorming the particular construction of piston wherein the pistoncomposed of the head and guide members and wrist pin bosses are cast asa unit and the guide members separated from the head proper to producethe spring guide members in such a manner that the entire piston can beconstructed out of aluminum and machined to the proper size withoutplacing the material under excessive strain thereby producing a pistonwhich will fit the cylinder to a nicety at a very small cost.

Other and further objects and advantages 3 of the invention will behereinafter set forth and the novel features thereof defined by theappended claims.

In the drawings,

Figure 1 is a side elevation of a piston 5 showing the first step in theoperation of forming the same; and

Figure 2 is a similar view showing the complete piston.

In carrying out my method of forming the piston as disclosed the same ispreferably cast of aluminum and comprises a cup shaped head 1 havingskirt portions 2 forming circular guide members which are connected to t2 disk portion of the head 1 by 5 arms 3, the arms being connected tothe 1920. Serial No. 396,556.

guide portions substantially mid-way their length and extending into thecup shape of the piston and connected at a point adjacent the outer edgethereof. The head of the piston is provided with wrist pin bosses 4between the guide members 2 havin supporting braces 5 and are soconstructe as to retard the travel of heat from the head to the wristpin bosses.

lieve itself and allows the two sections of the piston to finish inperfect alignment.

The detail construction of piston is fully disclosed in my companionapplication covering the piston construction and this application coversthe method and consists in casting a piston with a cup shaped head andcircular guide members connected to the disk of the head by arms andthen severing the guide members from the cup shaped head in order toproduce spring guide members.

From the foregoing description it will beseen that I have produced amethod of forming a spring piston which consists in casting a pistonwith a cup shaped head having circular guide members connected theretoby arms and then machining the entire surface of the piston in order toproduce a finished head with grooves for the piston ring and thensevering the skirt or guide portions of the head and grinding the guidemembers which are 'carried by the arms to the proper size in order toproduce spring guide members for allowing the same to expand andcontract.

Vhat I claim is 1. The method of forming a sprin piston consisting incasting a cup shape piston with guide members having a connection withthedisk portion of the cup shaped piston and then severing the guidemembers from the wall of the cup shaped head.

2. The method of forming a piston which consists in casting a cup shapedpiston with circular guide members extending from the walls thereofhaving a connection with the disk shaped portion'of the piston by arms,then machining the entire surface of the piston in order to produce ahead with ring grooves, then severing the guide members from the cupshaped piston and then grinding the guide members to the proper size.

3. The method of forming a spring piston I consisting in casting a cupshaped piston out of aluminum with guide members connected mid-way theirlength to the disk portion of the head by arms and then severing theguide members from the head proper.

4;. The method of forming a spring-piston which consists in casting acup shaped piston with circular skirt portions connected the cup shapedportion of the piston head,

and then grinding the guide members to the proper mm.

In testimony whereof I have hereunto affixed my signature in thepresence of two witnesses.

WALTER G. HEGINBOTTOM.

Witnesses:

WILLIAM L. TIKKA, G120. TAFT.

